Quantitative Raman Spectroscopic Determination of the Composition, Pressure, and Density of CO₂-CH₄ Gas Mixtures

Table 2

The F (CH₄)/F (CO₂) in ten CO₂-CH₄ gaseous mixtures at room temperature and pressures up to 40 MPa.

P (MPa)	X CH4 (mol%)	^aA (CH4)/ A (CO2)	F (CH4)/ F (CO2)
2	10	0.431	3.878
5		0.445	4.006
10		0.449	4.043
20		0.453	4.074
30		0.445	4.008
40		0.446	4.010
Avg.		0.448	4.031
2	20	0.994	3.978
5		1.037	4.147
10		1.078	4.314
20		1.055	4.219
30		1.059	4.235
40		1.063	4.250
Avg.		1.059	4.235
2	30	1.763	4.114
5		1.852	4.322
10		1.890	4.409
20		1.930	4.504
30		1.925	4.491
40		1.919	4.477
Avg.		1.925	4.491
2	40	2.873	4.309
5		2.976	4.463
10		3.021	4.531
20		3.021	4.531
30		3.027	4.540
40		3.044	4.565
Avg.		3.030	4.545
2	50	4.698	4.698
5		4.788	4.788
10		4.928	4.928
20		4.836	4.836
30		4.658	4.658
40		4.691	4.691
Avg.		4.728	4.728
2	60	6.643	4.429
5		6.919	4.613
10		7.072	4.714
20		7.165	4.777
30		7.176	4.784
40		7.198	4.799
Avg.		7.180	4.787
2	70	11.945	5.119
5		12.492	5.354
10		11.974	5.132
20		12.928	5.541
30		12.616	5.407
40		12.525	5.368
Avg.		12.690	5.430
2	80	18.170	4.542
5		18.541	4.635
10		18.808	4.702
20		19.427	4.857
30		19.652	4.913
40		19.516	4.879
Avg.		19.531	4.883
2	85	27.075	4.778
5		28.308	4.996
10		28.129	4.964
20		28.781	5.079
30		28.821	5.086
40		28.606	5.048
Avg.		28.736	5.071
2	90	39.812	4.424
5		41.345	4.594
10		42.173	4.686
20		46.208	5.134
30		45.496	5.055
40		44.950	4.994
Avg.		45.551	5.061

^aA is the Raman peak area.